Surface cleaning apparatus

ABSTRACT

A surface cleaning apparatus such as a hand vacuum cleaner comprises a first cyclone and at least one additional dirt separation unit. The at least one additional dirt separation unit is visible when the suction motor housing is removed from the hand vacuum cleaner.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing date of Canadian Patent Application No. 2658021, filed Mar. 11, 2009, entitled SURFACE CLEANING APPARATUS.

FIELD

The specification relates to surface cleaning apparatus and preferably to a surface cleaning apparatus that may be convertible to an upright or stick vacuum cleaner. In a particularly preferred embodiment, the specification relates to a cyclonic vacuum cleaners, and particularly, to cyclonic hand vacuum cleaners having a cyclone unit and an additional dirt separation member.

INTRODUCTION

The following is not an admission that anything discussed below is prior art or part of the common general knowledge of persons skilled in the art.

PCT publication WO 2008/009890 (Dyson Technology Limited) discloses a handheld cleaning appliance comprising a main body, a dirty air inlet, a clean air outlet and a cyclonic separator for separating dirt and dust from an airflow. The cyclone separator is located in an airflow path leading from the air inlet to the air outlet. The cyclonic separator is arranged in a generally upright orientation (i.e., the air rotates about a generally vertical axis in use). A base surface of the main body and a base surface of the cyclonic separator together form a base surface of the appliance for supporting the appliance on a surface. See also PCT publication WO 2008/009888 (Dyson Technology Limited) and PCT publication WO 2008/009883 (Dyson Technology Limited).

U.S. Pat. No. 7,370,387 (Black & Decker Inc.) discloses a hand-holdable vacuum cleaner that uses one or more filters and/or cyclonic separation device. and means for adjusting an angle of air inlet relative to a main axis of said vacuum cleaner. In particular, the vacuum cleaner further comprises a rigid, elongate nose having the air inlet at one end thereof, the nose being pivotal relative to a main axis of the vacuum cleaner through an angle of at least 135 degrees.

SUMMARY

The following introduction is provided to introduce the reader to the more detailed discussion to follow. The introduction is not intended to limit or define the claims.

According to one broad aspect, a surface cleaning apparatus, and preferably a hand vacuum cleaner is provided that has a cyclone and at least one additional air treatment member, such as a further cyclone or plurality of cyclones and/or a physical filter element, such as a foam filter. The surface cleaning apparatus is openable such as by removal of the suction motor or pivoting the suction motor to an open position. When the surface cleaning apparatus is opened, the additional air treatment member or members may be removed or serviced.

Accordingly, the surface cleaning apparatus, and preferably a hand vacuum cleaner may comprise a front end, a rear end and an air flow passage extending from a dirty air inlet to a clean air outlet. A first cyclone unit is positioned in the air flow passage. The first cyclone unit comprises at least one cyclone having a cyclone outlet and at least one dirt collection chamber. A suction motor is positioned in a suction motor housing. The hand vacuum cleaner further comprises at least one additional dirt separation unit provided in a chamber. The at least one additional dirt separation unit is visible when the chamber is opened by moving the suction motor housing. Preferably, the suction motor housing is removably mounted to the hand vacuum cleaner. In alternate embodiments, it may be openable, e.g., pivotally openable, but not removable.

The chamber is provided between the first cyclone unit and the suction motor when the suction motor housing is mounted to the hand vacuum cleaner and preferably in a space between the dirt stage cyclone air outlet and the air inlet of the suction motor. Accordingly a wall of the cyclone unit and/or a wall of the motor housing may be sized to define the chamber. The walls may be separable such that the interior of the chamber is accessible when the walls are separated.

In some examples, the at least one additional dirt separation unit comprises at least one of a pre-motor filter and a second cyclone unit. In some examples, the at least one additional dirt separation unit comprises a pre-motor filter and a second cyclone unit.

In some examples, the suction motor housing is removably mounted to the first cyclone unit. In some examples, first cyclone unit comprises a one piece assembly.

In some examples, the surface cleaning apparatus is removably mounted to a support structure that is pivotally mounted to a surface cleaning head, thereby forming an upright surface cleaning apparatus. For example, the upright surface cleaning apparatus may be a stick vacuum cleaner having a support structure, e.g., a support rod, pivotally mounted to any surface cleaning head known in the vacuum cleaner art. The surface cleaning apparatus may be a portable surface cleaning apparatus (e.g., hand or strap carriable while in use). Preferably the surface cleaning apparatus is a hand vacuum cleaner.

In some examples, an air flow path extends from a dirty air inlet of the surface cleaning head to the surface cleaning apparatus (e.g., the dirty air inlet of the surface cleaning apparatus) wherein the air flow path comprises a flexibly conduit of the upright surface cleaning apparatus. In such a mode, the surface cleaning apparatus (e.g., the hand vacuum cleaner) may contain part or all of the air treatment members of the upright surface cleaning apparatus. The surface cleaning apparatus may be operable while connected to the upright surface cleaning apparatus via the flexible conduit but removed from the support structure.

In some examples, the dirt collection chamber is removable from the motor housing as a sealed unit for emptying. In some examples, first cyclone unit is removable from the surface cleaning apparatus as a sealed unit for emptying.

In some examples, the first cyclone unit comprises a single cyclone and a single dirt collection chamber.

In some examples, the first cyclone unit has a rear end and the at least one additional dirt separation unit comprises a second cyclone unit provided on the rear end of the first cyclone unit.

In some examples, the first cyclone unit and the second cyclone unit are removable concurrently from the suction motor housing.

In some examples, the at least one additional dirt separation unit comprises a pre-motor filter provided in the chamber facing the cyclone air outlet.

In some examples, the pre-motor filter is mounted in the suction motor housing.

In some examples, the suction motor housing has a front end and a rear end, the front end of the suction motor housing is removably mounted to the first cyclone unit, and the rear end of the suction motor housing is removably mounted to a post motor filter housing.

In some examples, the at least one additional dirt separation unit comprises at least one pre-motor filter, and the first cyclone unit, the pre-motor filter and the suction motor are linearly aligned.

In some examples, the hand vacuum cleaner further comprises a post motor filter, and the first cyclone unit, the pre-motor filter, the suction motor and the post motor filter are linearly aligned.

In some examples, one of the first cyclone unit and the suction motor housing has a ring wall that is positioned exterior to an outer surface of the other of the first cyclone unit and the suction motor housing when the hand vacuum cleaner is assembled. The ring wall may be a continuous wall.

In some examples, the first cyclone unit and the suction motor housing are rotationally mounted together.

In some examples, the first cyclone unit and the suction motor housing are rotationally mounted together by a bayonet mount.

It will be appreciated that the vacuum cleaner may incorporate one or more of the features of each of these examples.

DRAWINGS

In the detailed description, reference will be made to the following drawings, in which:

FIG. 1 is a side plan view of an example of a hand vacuum cleaner;

FIG. 2 is a top plan view of the hand vacuum cleaner of FIG. 1;

FIG. 3 is a front plan view of the hand vacuum cleaner of FIG. 1;

FIG. 4 is a partially exploded rear perspective view of the hand vacuum cleaner of FIG. 1;

FIG. 5 is a partially exploded front perspective view of the hand vacuum cleaner of FIG. 1;

FIG. 6 is a cross section taken along line 6-6 in FIG. 2;

FIG. 7A is a bottom perspective view of the hand vacuum cleaner of FIG. 1;

FIG. 7B is a rear perspective view of the hand-vacuum cleaner of FIG. 1, showing a suction motor removed from the hand vacuum cleaner;

FIG. 7C is a front perspective view of the hand-vacuum cleaner of FIG. 1, showing a suction motor removed from the hand vacuum cleaner;

FIG. 7D is a rear perspective view of the hand-vacuum cleaner of FIG. 1, showing a post-motor filter housing removed from a suction motor housing;

FIG. 8 is a cross section showing an alternate example of a hand vacuum cleaner;

FIG. 9 is an exploded side perspective view of a portion of the hand vacuum cleaner of FIG. 8;

FIG. 10 is an exploded bottom perspective view of a portion of the hand vacuum cleaner of FIG. 8;

FIG. 11 is an exploded bottom perspective view of the hand vacuum cleaner of FIG. 8; and

FIG. 12 is a perspective illustration of the hand vacuum cleaner of FIG. 1 mounted to an upright vacuum cleaner.

DESCRIPTION OF VARIOUS EXAMPLES

Various apparatuses or methods will be described below to provide an example of each claimed invention. No example described below limits any claimed invention and any claimed invention may cover processes or apparatuses that are not described below. The claimed inventions are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below. It is possible that an apparatus or process described below is not an embodiment of any claimed invention.

In the drawings attached hereto, the surface cleaning apparatus is exemplified as a hand vacuum cleaner comprising one or two cyclonic stages. It will be appreciated that the vacuum cleaner 100 may be of various configurations (e.g., different positioning and/or orientation of the cyclonic stages and the suction motor and differing cyclonic stages that may comprise one or more cyclones and one or more filters). The surface cleaning apparatus may be any portable surface cleaning apparatus that comprises one or more air treatment members and a suction motor in a self contained unit and may be a pod or hand vacuum cleaner or various designs.

Referring to FIGS. 1 to 7D, a first example of a vacuum cleaner 100 is shown. The vacuum cleaner 100 is a hand vacuum cleaner, and is movable along a surface to be cleaned by gripping and maneuvering handle 102. The vacuum cleaner includes an upper portion 104, a lower portion 106, a front end 108, and a rear end 110. In the example shown, handle 102 is provided at the upper portion 104. In alternate examples, handle 102 may be provided elsewhere on the vacuum cleaner 100, for example at the rear end 110, and may be of any design.

In the example shown, the vacuum cleaner 100 comprises a nozzle 112 and a first cyclone unit 114, which together preferably form a surface cleaning head 116 of the vacuum cleaner 100. As exemplified, the surface cleaning head 116 is preferably provided at the front end 108 of the vacuum cleaner 100.

Nozzle 112 engages a surface to be cleaned, and comprises a dirty air inlet 118, through which dirty air is drawn into the vacuum cleaner 100. An airflow passage extends from the dirty air inlet 118 to a clean air outlet 120 of the cleaner 100. In the example shown, clean air outlet 120 is at the rear end 110 of the cleaner 100.

Cyclone unit 114 is provided in the airflow passage, downstream of the dirty air inlet 118. Cyclone unit 114 has a front 194, and a rear 192. In the example shown, the cyclone unit 114 is a one piece assembly comprising one cyclone 122, and one dirt collection chamber 124, which are integrally formed. In alternate examples, the cyclone unit 110 may include more than one cyclonic stage, wherein each cyclonic stage comprises one or more cyclones and one or more dirt chambers. Accordingly, the cyclones may be arranged in parallel and/or in sequence. Further, in alternate examples, the cyclone 122 and dirt collection chamber 124 may be separately formed.

In the example shown, the nozzle 112 is preferably positioned at the lower portion 106 of the vacuum cleaner 100. Preferably, as exemplified, nozzle 112 is positioned at the bottom of the vacuum cleaner 100, and, preferably, beneath the cyclone unit 114. However, it will be appreciated that nozzle 112 may be connected to the cyclone unit or dirt collection chamber at alternate locations.

Preferably, as exemplified, nozzle 112 may be on lower surface 157 of cyclone unit 114. In a particularly preferred design, the upper wall 126 of the nozzle may be a lower wall 119 of the cyclone unit 114. As shown in FIG. 6, dirt chamber 124 surrounds the lower portion of cyclone 122. Accordingly, the upper wall of nozzle 112 may be part of the lower wall of the dirt chamber. It will be appreciated that if dirt chamber 124 does not extend around the lower portion of cyclone 122, then the upper wall of nozzle 112 may be part of a lower wall of cyclone 122.

Preferably, as exemplified, the nozzle 112 is fixedly positioned at the lower portion 106 of the vacuum cleaner 100. That is, the nozzle 112 is not movable (e.g., rotatable) with respect to the remainder of the vacuum cleaner 100, and is fixed at the lower portion 106 of the vacuum cleaner 100.

As shown in FIGS. 3 and 5, nozzle 112 has a width W_(N), and cyclone unit 114 has a width W_(C). In the example shown, W_(N), and W_(C) are about the same. An advantage of this design is that the nozzle 112 may have a cleaning path that is essentially as wide as the hand vacuum itself.

Preferably, nozzle 112 comprises an airflow chamber 136 wherein at least a portion, and preferably a majority, of the lower surface of the airflow chamber is open. Such a design is exemplified in FIG. 7A, wherein nozzle 112 comprises an upper nozzle wall 126. In the example shown, as mentioned hereinabove, the upper nozzle wall 126 comprises a portion 119 of a wall 115 of the cyclone unit.

Preferably, as exemplified, one or more depending walls 128 extend downwardly from the upper nozzle wall 126. The depending wall 128 is preferably generally U-shaped. In one embodiment, a depending wall is provided rearward of opening 138. In other embodiments, depending walls may alternately or in addition be provided on the lateral sides of opening 138. Further, depending walls 128 may extend a substantial distance to the front end 108 and, preferably, essentially all the way to front end 108. The depending wall may be continuous to define a single wall as shown, or may be discontinuous. The depending wall is preferably rigid (e.g., integrally molded with cyclone unit 114). However, it may be flexible (e.g., bristles or rubber) or moveably mounted to cyclone unit 114 (e.g., hingedly mounted).

Preferably, the lower end 132 of depending wall 128 is spaced above the surface being cleaned when the hand vacuum cleaner is placed on a surface to be cleaned. As exemplified in FIG. 6, when vacuum cleaner 100 is placed on a floor F, lower end 132 of depending wall 128 is spaced a distance H above the floor. Preferably distance H is from 0.01 to 0.175 inches, more preferably from 0.04 to 0.08 inches.

The height of the depending wall (between upper nozzle wall 126 and lower end 132) may vary. In some examples, the depending wall may have a height of between about 0.05 and about 0.875 inches, preferably between about 0.125 and about 0.6 inches and more preferably between about 0.2 and about 0.4 inches. The height of depending wall may vary but is preferably constant.

As exemplified, the open end of the U-shape defines an open side 130 of the nozzle 114, and forms the dirty air inlet 118 of the cleaner 100. In the example shown, the open side 130 is provided at the front of the nozzle 114. In use, when optional wheels 135 are in contact with a surface, the open side 130 sits above and is adjacent a surface to be cleaned (e.g. floor F). As mentioned hereinabove, preferably, lower end 132 of depending walls 128 is spaced above floor F. Accordingly, some air may enter nozzle 114 by passing underneath depending wall 132. In such a case, the primary air entry to nozzle 114 is via open side 130 so that dirty air inlet 118 is the primary air inlet, with a secondary air inlet being under depending wall 128.

In the example shown, the lower end 132 of the depending wall 128 defines an open lower end 134 of the nozzle 114. The open lower end 134 preferably extends to the front end 108 of the cleaner 108, and merges with the open side 130. In use, the exemplified nozzle has an open lower end 134 that faces a surface to be cleaned.

In the example shown, a plurality of wheels 135 are mounted to the depending wall 128, and extend lower than the lower end 132 of the depending wall 128. Accordingly, in use, when wheels 135 are in contact with a surface, the lower end 132 of the depending wall 128 is preferably spaced from the surface to be cleaned, and the space between the lower end of the depending wall 128 and the surface to be cleaned form the secondary dirty air inlet to the vacuum cleaner 100. It will be appreciated that wheels 135 are optional. Preferably, wheels 135 are positioned exterior to the airflow path through nozzle 112, e.g., laterally outwardly from depending wall 128. Preferably a pair of front wheels 135 are provided. Preferably, the wheels are located adjacent front end 108. Optionally, one or more rear wheels 180 may be provided. In an alternate embodiment, no wheels may be provided.

The upper nozzle wall 126, depending wall 128, and open lower end 134 of the nozzle 112 define the open sided airflow chamber 136 of the nozzle. In use, when wheels 135 are in contact with a horizontal surface, the nozzle 112 and the airflow chamber 136 extend generally horizontally, and preferably linearly along a nozzle axis 113 (see FIG. 7A).

An opening 138 may be provided in the upper nozzle wall 126, and is in communication with the airflow chamber 136. Opening 138 may be of any size and configuration and at various locations in upper nozzle wall 126. In use, when wheels 135 are in contact with a surface, the opening 138 faces a surface to be cleaned, air enters the dirty air inlet 118, passes horizontally through the airflow chamber 136, and passes into the opening 138. Opening 138 is in communication with a cyclone inlet passage 139, which is in communication with a cyclone air inlet 140 of cyclone 122.

Cyclone 122 may of any configuration and orientation. Preferably, cyclone 122 comprises a chamber wall 142, which in the example shown, is cylindrical. The cyclone chamber is located inside chamber wall 142. The cyclone 122 extends along an axis 123, which, in the example shown, is preferably parallel to the nozzle axis, and preferably extends generally horizontally when cleaner 100 is in use and wheels 135 are seated on a surface. The cyclone 122 has an air inlet 140 and an air outlet 145, which preferably are at the same end of cyclone 122. Preferably the air inlet and the air outlet are distal to front end 108. The cyclone air inlet and cyclone air outlet may be of any configuration known in the art and the cyclone air outlet may be covered by a screen or shroud or filter as is known in the art. Preferably, the dirt outlet is at an opposed end.

As exemplified, the cyclone air inlet 140 is defined by an aperture in the chamber wall 142. The cyclone inlet 140 is preferably at the rear end 198 of the cyclone 122. As can be seen in FIG. 5, the inlet passage 139 is configured such that air enters the cyclone 122 in a tangential flow path, e.g., passage 139 may be arcuate. The air travels in a cyclonic path in the cyclone, and dirt in the air is separated from the air. The air exits the cyclone via an outlet passage 144, through outlet 145. Outlet 145 is preferably defined in a rear wall 179 of the cyclone unit 114.

As exemplified in FIG. 6, a plate 174 may be provided adjacent outlet passage 144, spaced from and facing the inlet 176 to outlet passage 144. Plate 174 may be mounted to cyclone 122 via legs 178. In the example shown, plate 174, and legs 178 form an assembly 182 that is removably mounted in cyclone 122. In some examples, a screen may be mounted around legs 178.

The dirt that is separated from the air exits the cyclone via dirt outlet 146, and enters dirt collection chamber 124. Dirt outlet is preferably at the front 196 of the cyclone 122, and further, is at the front end 108 of the cleaner 100. The dirt collection chamber may be internal or external to the cyclone chamber. Preferably, as exemplified, the dirt collection chamber is external. The dirt collection chamber may be in communication with the cyclone chamber by any means known in the art. Accordingly, one or more dirt outlets may be provided. Preferably, the dirt outlet is at the end opposed to the air inlet and, preferably, the dirt outlet is at the front end 108.

In the example shown, dirt collection chamber 124 preferably comprises two portions. A first portion 148 is provided immediately adjacent the dirt outlet 146, and is at the front end 108 of the cleaner 100. A second portion 150 is concentric with the cyclone 122. A lower portion 152 of the second portion 150 is below the cyclone. As exemplified, nozzle 112 is positioned below first portion 148, and lower portion 152. Accordingly, dirt chamber 124 may comprise an annular chamber surrounding the cyclone 122.

A separation plate 154 may be provided in the dirt collection chamber 124, and may be mounted in facing relation to and adjacent the dirt outlet 146. The separation plate 154 aids in preventing dirt in dirt collection chamber 124 from re-entering cyclone 122. Preferably, plate 154 is spaced from dirt outlet 146 and faces dirt outlet 146. Plate 154 may be mounted by any means to any component in cyclone unit 114. As exemplified, the separation plate is preferably mounted on an arm 156, which extends from a front wall 158 at the front end 108 of the cleaner 100.

Cyclone unit 114 may be emptied by any means known in the art. For example, one of the ends of the cyclone unit 114 may be openable and/or removable. As exemplified in FIGS. 4 and 5, front wall 158 is pivotally mounted to the cyclone unit wall 115 and serves as an openable door of the dirt chamber 124, such dirt collection chamber 124 is openable, and dirt collection chamber 124 may be emptied. The dirt collection chamber is preferably openable both when the dirt collection chamber is mounted to the hand vacuum cleaner, or when it is optionally removed. When front wall 158 is pivoted away from the remainder of the cyclone unit 114, separation plate 154, if mounted thereon, also pivots away from the remainder of the cyclone unit. A latch 159 or other securing member or members may be provided, which secures front wall 158 to wall 115. In alternate examples, front wall 158 may be removable from cyclone unit wall 115, or the rear wall 179 of the cyclone unit 114 may be openable.

The rear portion of the dirt collection chamber 124 may be closed by wall 179.

The clean air exiting cyclone 122 passes through outlet 145 of outlet passage 144, exits surface cleaning head 116, and passes into the cleaner body 160. In the example shown, the cleaner body 160 is positioned rearward of the surface cleaning head 116.

The cleaner body comprises a suction motor housing 168, which has a front end 167, and a rear end 169. The suction motor housing 168 houses a suction motor 164. The suction motor 164 may be any type of suction motor. The suction motor draws air into the dirty air inlet 118 of the cleaner 100, through the airflow path past the suction motor 164, and out of the clean air outlet 120. The suction motor 164 has a motor axis 165. In the example shown, the motor axis 165 and the cyclone axis 123 preferably extend in the same direction and are preferably generally parallel.

In the example shown, the vacuum cleaner 100 further comprises an additional dirt separation unit 121. As exemplified in FIGS. 1-7B, the additional dirt separation unit 121 is provided in a chamber of the cleaner body, and more particularly, mounted in the suction motor housing.

In the example shown in FIGS. 1-7B, the additional dirt separation unit is a pre-motor filter 162. Pre-motor filter 162 is provided in the airflow path preferably adjacent and downstream of the outlet passage 144, and preferably facing the outlet 145. More particularly, pre-motor filter 162 is provided in a chamber 161 of the motor housing 168 between the motor and the first cyclone unit 114. In the exemplified embodiment, cyclone unit 114, pre-motor filter 162, and the suction motor 164 are preferably linearly aligned. That is, they all extend along a common axis 125 of the cleaner 100.

Pre-motor filter 162 serves to remove remaining particulate matter from air exiting the cyclone 122, and may be any type of filter, such as a foam filter. One or more filters may be used. In the exemplified embodiments, the vacuum cleaner has a linear configuration. If the vacuum cleaner is of a non-linear configuration, then pre-motor filter 162 need not be located adjacent outlet passage 144.

The cleaner body 160 further comprises an optional post-motor filter housing 170. A post motor filter 166 is provided in the post-motor filter housing 170. The post motor filter 166 is provided in the airflow path downstream of, and preferably adjacent, the suction motor 164. In the example shown, the post motor filter 166 is linearly aligned with the cyclone unit 114, pre-motor filter 162, and motor 164, along axis 125. Post motor filter 166 serves to remove remaining particulate mater from air exiting the cleaner 100. Post-motor filter 166 may be any type of filter, such as a HEPA filter.

Clean air outlet 120 is provided downstream of post-motor filter 166. Clean air outlet 120 may comprise a plurality of apertures formed in housing 170.

Referring to FIG. 7B, the suction motor housing 168 is removably mounted to the hand vacuum cleaner 100. In the example shown, the suction motor housing 168 is removably mounted to the first cyclone unit 114 of the vacuum cleaner 100, and more particularly, the front end 167 of the suction motor housing 168 is removably mounted to the first cyclone unit 114. When the suction motor housing 168 is removed from the hand vacuum cleaner 100, the additional dirt separation unit 121 is visible. That is, as shown in FIG. 7B, the pre-motor filter 162 is visible when suction motor housing 168 is removed from the vacuum cleaner 100. Accordingly, the pre-motor filter 162 may be removed, serviced, changed, or cleaned.

In the example shown, the cyclone unit 114 comprises the dirt collection chamber 124. Accordingly, when the cyclone unit 114 is removed from the suction motor housing 168, the dirt collection chamber 124 is removed from the suction motor housing. Further, as shown in FIG. 7C, the cyclone unit 114, and the dirt collection chamber 124, are preferably removed as a sealed unit for emptying. That is, cyclone unit 114 is sealed, except for the fluid flow passages leading to and from the first cyclone unit 114 (i.e. opening 138 and outlet 145). In order to empty the dirt collection chamber 124, the front wall 158 may be opened, and the dirt may be emptied from dirt chamber 124. Cyclone unit 114 may be emptied by any other means known in the vacuum cleaner arts.

The motor housing 168 may be removably mounted to the surface cleaning apparatus 100 in any manner. For example, it may be mounted thereto by a screw mount, a bayonet mount and/or hand operable mechanical fasteners such as latches.

Preferably, the cyclone unit 114 and the motor housing 168 are configured such that one component may be rotated on the other unit to align the mounting or engagement members. Preferably, the rear end of the suction motor housing is configured such that the rear end may be placed on a horizontal surface (e.g., a floor or a table top) and stood upright (i.e., with the end of motor housing adjacent cyclone unit 114 facing up). In such an orientation, the cyclone unit may be placed on top of motor housing 168 and rotated until the cyclone unit is locked into place on the motor housing.

Accordingly,in order to removably mount the motor housing 168 to the surface cleaning apparatus, one of the cyclone unit 114 and the motor housing 168 may have a ring wall 147 that is positioned exterior to an outer surface of the other of the first cyclone unit and the suction motor housing when the hand vacuum cleaner 100 is assembled. In the example shown, the cyclone unit 114 has the ring wall 147 at the rear end 192 thereof, and the front 167 of the motor is insertable into the ring wall. In the example shown, the ring wall 147 is a continuous wall. In alternate example, the ring wall 147 may be discontinuous.

Further, the cyclone unit 114 and the motor housing 168 are preferably rotationally mounted together. For example, as shown, the motor housing 168 a first mounting member 175, and the cyclone unit 114 has a second mounting member 173. The first 173 and second 175 mounting members are releasably engageable with each other when the front 167 of the motor housing 168 is inserted into the ring wall 147, and the motor housing 168 is, e.g., rotated with respect to the cyclone unit 114. In the example shown, the first 173 and second 175 mounting members comprise a bayonet mount. In alternate examples, the first and second mounting members may be another type of mounting member, such as mating screw threads.

Referring to FIG. 7D, the suction motor housing 168 is preferably removably mounted to the post-motor filter housing 170. More particularly, the rear end 169 of the suction motor housing 168 is preferably removably mounted to the post-motor filter housing. The suction motor housing 168 and the post-motor filter housing may be removably mounted together by any means including those referred to for removably securing motor housing 168 to cyclone unit 114.

One or more additional wheels 180 may be mounted to motor housing 168, preferably at lower portion 106, and may be used in conjunction with wheels 135. Preferably, a single rear wheel 180 is provided. Preferably, rear wheel 180 is located on a centre line of the vacuum cleaner and rearward of the depending wall 128.

Referring now to FIGS. 8 to 11, in which like numerals refer to like features, with the first digit incremented to 8 to refer to the figure number, an alternate example of a hand vacuum cleaner 800 is shown. This embodiment shows various alternate constructions, one or more of which may be used in addition to or in replacement of, those of the embodiment of FIGS. 1-7.

For example, nozzle 812 is an enclosed air flow passage as opposed to an open sided air flow chamber. Nozzle 812 comprises a lower wall 837, which closes lower end 834.

In this example, front wall 858 may be pivotally mounted to wall 815, as shown in FIGS. 9 to 11, or may not be pivotally mounted to wall 815. For example, as shown in FIG. 8, wall surface cleaning head 816 is pivotally mounted to body 860.

Further, in this example, the vacuum cleaner 800 comprises two additional dirt separation units 821, including a second cyclone unit 851 downstream of the first cyclone unit 114, as well as a pre-motor filter 862 downstream of the second cyclone unit 851. However, only the second cyclone unit may be provided

In the example shown, the second cyclone unit 851 comprises a plurality of second stage cyclones arranged in parallel. The second cyclone unit 851 has an inlet 853 in communication with each second stage cyclone, and each second stage cyclone has an outlet 855. In alternate examples, the second cyclone unit 851 may comprise only a single cyclone, or multiple cyclones arranged in series.

While both the pre-motor filter 862 and the second cyclone unit 851 are provided in the chamber, preferably each of the second air treatment units is visible when the motor housing is opened. Accordingly, one unit may be mounted to the motor housing and another to the cyclone unit 114. Preferably second cyclone unit 851 is removably mounted to cyclone unit 114, such as being mounted to the rear 892 thereof.

In this example, similarly to vacuum cleaner 100, suction motor housing 868 is removably mounted to vacuum cleaner 800. Accordingly, when suction motor housing 868 is removed from the hand vacuum cleaner 800, both pre-motor filter 862 and second cyclone unit 851 are visible. Second cyclone unit 851 may be openable and therefore emptyable when mounted to cyclone unit 114 and/or when removed therefrom. Second cyclone unit 851 may be removable mounted by any means known in the art such as a bayonet mount, a screw mount or hand operable mechanical fasteners.

Accordingly, the first cyclone unit 814 and the second cyclone unit 851 are optionally removable concurrently from the suction motor housing 868, or separately.

It will be appreciated that in alternate examples, the additional dirt separation unit may comprise only a second cyclone unit, without a pre-motor filter.

As shown in FIG. 12, in addition to being usable as a hand vacuum cleaner, surface cleaning apparatus 100 is mountable to an upright vacuum cleaner 1200 as a removable pod. For example, as shown, surface cleaning apparatus 100 is mounted to a support 1202 of vacuum cleaner 1200, and is in fluid communication with a surface cleaning head 1204 of vacuum cleaner 1200. 

1. A surface cleaning apparatus comprising: (a) a front end and a rear end: (b) an air flow passage extending from a dirty air inlet to a clean air outlet; (c) a first cyclone unit positioned in the air flow passage, the first cyclone unit comprising at least one cyclone having a cyclone outlet and at least one dirt collection chamber; (d) a suction motor positioned in a suction motor housing; and, (e) at least one additional dirt separation unit provided in a chamber, wherein the at least one additional dirt separation unit is visible when the chamber is opened by moving the suction motor housing.
 2. The surface cleaning apparatus of claim 1 wherein the suction motor housing is removeably mounted to the hand vacuum cleaner.
 3. The surface cleaning apparatus of claim 1 wherein the at least one additional dirt separation unit comprises at least one of a pre-motor filter and a second cyclone unit.
 4. The surface cleaning apparatus of claim 2 wherein the at least one additional dirt separation unit comprises a pre-motor filter and a second cyclone unit.
 5. The surface cleaning apparatus of claim 1 wherein the suction motor housing is removably mounted to the first cyclone unit.
 6. The surface cleaning apparatus of claim 1 wherein the first cyclone unit comprises a one piece assembly.
 7. The surface cleaning apparatus of claim 1 wherein the surface cleaning apparatus is removably mounted to a support structure that is pivotally mounted to a surface cleaning head.
 8. The surface cleaning apparatus of claim 7 further comprising an air flow path extending from a dirty air inlet of the surface cleaning head to the surface cleaning apparatus, the air flow path comprising a flexibly conduit.
 9. The surface cleaning apparatus of claim 1 wherein the surface cleaning apparatus comprises a hand vacuum cleaner.
 10. The surface cleaning apparatus of claim 1 wherein the dirt collection chamber is removable from the motor housing as a sealed unit for emptying.
 11. The surface cleaning apparatus of claim 1 wherein the first cyclone unit is removable from the surface cleaning apparatus as a sealed unit for emptying.
 12. The surface cleaning apparatus of claim 1 wherein the first cyclone unit comprises a single cyclone and a single dirt collection chamber.
 13. The surface cleaning apparatus of claim 1 wherein the first cyclone unit has a rear end and the at least one additional dirt separation unit comprises a second cyclone unit provided on the rear end of the first cyclone unit.
 14. The surface cleaning apparatus of claim 13 wherein the first cyclone unit and the second cyclone unit are removable concurrently from the suction motor housing.
 15. The surface cleaning apparatus of claim 1 wherein the at least one additional dirt separation unit comprises a pre-motor filter provided in the chamber facing the cyclone air outlet.
 16. The surface cleaning apparatus of claim 15 wherein the pre-motor filter is mounted in the suction motor housing.
 17. The surface cleaning apparatus of claim 1 wherein the suction motor housing has a front end and a rear end, the front end of the suction motor housing is removably mounted to the first cyclone unit and the rear end of the suction motor housing is removably mounted to a post motor filter housing.
 18. The surface cleaning apparatus of claim 1 wherein the at least one additional dirt separation unit comprises at least one pre-motor filter, and the first cyclone unit, the pre-motor filter and the suction motor are linearly aligned.
 19. The surface cleaning apparatus of claim 18 further comprising a post motor filter and the first cyclone unit, the pre-motor filter, the suction motor and the post motor filter are linearly aligned.
 20. The surface cleaning apparatus of claim 1 wherein one of the first cyclone unit and the suction motor housing has a ring wall that is positioned exterior to an outer surface of the other of the first cyclone unit and the suction motor housing when the surface cleaning apparatus is assembled.
 21. The surface cleaning apparatus of claim 20 wherein the first cyclone unit and the suction motor housing are rotationally mounted together.
 22. The surface cleaning apparatus of claim 21 wherein the first cyclone unit and the suction motor housing are rotationally mounted together by a bayonet mount.
 23. The surface cleaning apparatus of claim 22 wherein the ring wall is a continuous wall. 